To help with the understanding of dither, I am posting an explanation, of how signal details smaller than the quantization level are retained, after quantization, when Dither Noise is added to the source material. A small signal detail with height less than the quantization level, and centred half way between two quantization steps, is too small to cross a quantization step. It is lost when the waveform is quantized. With a Dither Noise waveform added, the height of the two waveforms summed is occasionally greater than the quantization level. At these occasional points the waveform crosses a quantization step. So now when this waveform is quantized, although the result is noisy, the shape of the original signal detail is retained. Discussion invited.

Spatial dither:In a video feed spatial dither can be implemented by setting adjacent pixels that cannot be perfectly represented to different values and then altering these values in time depending on which is closest to the orginial value (temporal dither) In audio we use this temporal dither.

How weird would be to use the multiple speaker channels for spatial dither?